A new research project using mathematical models has indicated that COVID-19 may become merely a seasonal flu, inflicting mild symptoms.
The investigation, led by scientists at the University of Utah, has signified that the COVID-19 causing SARS-CoV-2 may lose some of its deadly characteristics over time, becoming more akin to a seasonal flu, with mild symptoms of coughing and sniffling.
The study is published in the journal Viruses.
Fred Adler, a professor of mathematics and biology at the University of Utah, said: “This shows a possible future that has not yet been fully addressed. Over the next decade, the severity of COVID-19 may decrease as populations collectively develop immunity.”
Analysing pandemic scenarios
The team have suggested that the adaptations of the disease are dependent on modifications to our immune system instead of the evolution of the virus itself. To trial this hypothesis, the researchers created a mathematical model comprised of evidence of the body’s response to SARS-CoV-2 and data from the pandemic to create various scenarios potentially implemented by the virus.
These scenarios were: a probable dose-response between disease severity and exposure to the virus, people exposed to small doses will contract mild symptoms and shed small amounts of the virus, adults with stronger doses will display severe symptoms and shed more considerably, masks and social distancing mitigate spreading, children will be less likely to develop severe symptoms, and vaccinated adults protected from severe disease.
The mathematical model revealed that the amalgamation of three mechanisms created a situation where a section of the population will become predisposed to mild COVID-19 symptoms over the long term, meaning that it would be regarded similarly to other seasonal influenzas.
Adler said: “At the beginning of the pandemic, no one had seen the virus before. Our immune system was not prepared. The models show that as more adults become partially immune, whether through prior infection or vaccination, severe infections all but disappear over the next decade. Eventually, the only people who will be exposed to the virus for the first time will be children and they’re naturally less prone to severe disease.”
Alexander Beams, the corresponding author of the study, said: “The novel approach here is to recognise the competition taking place between mild and severe COVID-19 infections and ask which type will get to persist in the long run. We’ve shown that mild infections will win, as long as they train our immune systems to fight against severe infections.”
“Our next step is comparing our model predictions with the most current disease data to assess which way the pandemic is going as it is happening. Do things look like they’re heading in a bad or good direction? Is the proportion of mild cases increasing? Knowing that might affect decisions we make as a society,” added Adler.
